Kia Optima — MPG & Fuel Costs 2025
Kia's executive saloon and estate, delivering supreme highway comfort, a long 7-year warranty, and highly frugal diesel running costs.
TL;DR
33 MPG
Real-world petrol
52 MPG
Real-world diesel
70L
Tank capacity
£95.76
Full tank (petrol)
18.8p
Per mile (petrol)
Real-World Fuel Economy: The Kia Optima achieves an estimated 33 MPG (petrol) and 52 MPG (diesel) in real-world UK driving conditions, accounting for a 12% WLTP real-world penalty.
Forecourt Fuel Cost: Refueling the 70-litre tank completely costs approximately £95.76 (petrol) or £99.47 (diesel) at average UK fuel price rates.
Fuel economy at a glance
33
Real-world MPG
Petrol
39.2
Official WLTP
Petrol
52
Real-world MPG
Diesel
61.4
Official WLTP
Diesel
Annual fuel costs by mileage
| Annual mileage | Petrol | Diesel |
|---|---|---|
| 5,000 miles/yr | £942 | £621 |
| 7,400 miles/yr(UK average) | £1395 | £919 |
| 10,000 miles/yr | £1885 | £1242 |
| 15,000 miles/yr | £2827 | £1863 |
| 20,000 miles/yr | £3769 | £2485 |
| Full tank (70L) | £95.76 | £99.47 |
| Cost per mile | 18.8p | 12.4p |
Based on UK average fuel prices: petrol 136.8p/L · diesel 142.1p/L. Prices updated regularly.
How does the Optima compare?
Tips to get better MPG from your Optima
Utilize Eco mode to optimize throttle response and transmission shifts.
Use gear ratios sensibly; the CRDi diesel works best when cruising at low revs.
Clean out heavy cargo from the boot to preserve fuel economy.
Is the cheaper petrol station worth it?
In a Kia Optima achieving ~33 MPG real-world, if you fill 56 litres and the alternative station is 10p/litre cheaper:
£5.60
Gross saving on fuel
£0.57
Cost of 3-mile detour
£5.03
Net saving ✓
You could drive up to 30 miles round-trip before the saving disappears entirely.
Calculate for your exact situationPopular variants
Frequently asked questions
What is the real-world MPG of the Kia Optima?
The Kia Optima achieves approximately 33 MPG in real-world petrol driving — around 12% lower than the official WLTP figure of 39.2 MPG due to real driving conditions. Diesel variants achieve around 52 MPG real-world.
How much does it cost to fill a Kia Optima?
The Kia Optima has a fuel tank of 70 litres. At the UK average of 136.8p/litre for petrol, a full tank costs approximately £95.76. Diesel costs approximately £99.47 for a full tank.
What is the annual fuel cost for a Kia Optima?
At the UK average annual mileage of 7,400 miles and current petrol price of 136.8p/litre, a Kia Optima costs approximately £1395 per year in fuel. At 10,000 miles/year the cost rises to £1885. Actual costs vary with your driving style and mileage.
Is it worth driving to a cheaper petrol station in a Kia Optima?
In a Kia Optima doing ~33 MPG real-world, driving 3 miles round-trip to save 10p/litre on a 56-litre fill nets approximately £5.03 after the extra fuel cost. You could drive up to 30 miles before the saving is eaten up. Use the WorthThePump calculator for your exact situation.
How much does the Kia Optima cost per mile in fuel?
The Kia Optima costs approximately 18.8p per mile in petrol at current UK prices. Over a typical commute of 30 miles per day, that is approximately £5.64 per day in fuel.
What is the WLTP MPG figure for the Kia Optima?
The official WLTP fuel economy figure for the Kia Optima is 39.2 MPG. However, real-world MPG is typically 10–15% lower than WLTP due to cold starts, air conditioning, motorway speeds, and varying loads. WorthThePump uses a 12% real-world penalty to give a more accurate estimate.
Related guides
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